Senate Dems to try passing debt ceiling increase

House Speaker John Boehner of Ohio arrives on Capitol Hill in Washington, Monday, Oct. 7, 2013. The Republican-controlled House and the Democrat-controlled Senate are at an impasse, neither side backing down, after House GOP conservatives linked the funding bill to President Obama's existent health care law. (AP Photo/J. Scott Applewhite)
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House Speaker John Boehner of Ohio arrives on Capitol Hill in Washington, Monday, Oct. 7, 2013. The Republican-controlled House and the Democrat-controlled Senate are at an impasse, neither side backing down, after House GOP conservatives linked the funding bill to President Obama's existent health care law. (AP Photo/J. Scott Applewhite)
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Normally packed with tourists, the stairs leading from the Capitol Visitors Center up to the Capitol Rotunda are empty as the government shutdown enters a second week, Monday, Oct. 7, 2013, in Washington. The government partially shut down last week amid Washington gridlock and faces a make-or-break deadline later this month about the nation's borrowing power. Republicans have refused to budge without concessions on Democrats' health care law. Democrats have resisted GOP efforts to dismantle tha— AP

Normally packed with tourists, the stairs leading from the Capitol Visitors Center up to the Capitol Rotunda are empty as the government shutdown enters a second week, Monday, Oct. 7, 2013, in Washington. The government partially shut down last week amid Washington gridlock and faces a make-or-break deadline later this month about the nation's borrowing power. Republicans have refused to budge without concessions on Democrats' health care law. Democrats have resisted GOP efforts to dismantle tha
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Rep. Louie Gohmert, R-Texas, escorts a group of constituents through the Capitol Rotunda during a lull in activity in the House of Representatives, Monday, Oct. 7, 2013, in Washington. The government partially shut down last week amid Washington gridlock and faces a make-or-break deadline later this month about the nation's borrowing power. (AP Photo/J. Scott Applewhite)— AP

Rep. Louie Gohmert, R-Texas, escorts a group of constituents through the Capitol Rotunda during a lull in activity in the House of Representatives, Monday, Oct. 7, 2013, in Washington. The government partially shut down last week amid Washington gridlock and faces a make-or-break deadline later this month about the nation's borrowing power. (AP Photo/J. Scott Applewhite)
/ AP

WASHINGTON 
Democrats controlling the Senate are planning to try to pass a stand-alone measure to increase the government's borrowing cap, challenging Republicans to a filibuster showdown that could unnerve financial markets as the deadline to a first-ever default on U.S. obligations draws closer.

A spokesman said Senate Majority Leader Harry Reid could unveil the measure as early as Tuesday, setting the table for a test vote later in the week. The measure is expected to provide enough borrowing room to last beyond next year's election, which means it likely will permit $1 trillion or more in new borrowing above the current $16.7 trillion debt ceiling that the administration says will be hit on Oct. 17.

The development came as a partial shutdown of the government enters its second week with no end in sight.

It's not clear whether Reid's gambit will work. Republicans are expected to oppose the measure if it doesn't contain budget cuts to make a dent in deficits. The question is whether Republicans will filibuster the measure.

Until recently, debt limit increases have not been the target of filibusters; the first in memory came four years ago, when Democrats controlled the Senate with a filibuster-proof 60 votes.

Many Republicans in the Senate, including Minority Leader Mitch McConnell of Kentucky and Whip John Cornyn of Texas, have voted for so-called clean debt limit increases during Republican administrations.

Some Republicans seemed wary of participating in a filibuster that could rattle the stock and bond markets.

"We shouldn't be dismissing anything out of hand, whether it's the debt ceiling or what we're going to do with this government shutdown," Sen. Lisa Murkowski, R-Alaska, said. "We've got a situation where you've got a calendar running, you've got people who are frustrated and upset, so let's figure it out."

The impasse over the shutdown - sparked by House Republicans' insistence that a temporary funding bill contain concessions on President Barack Obama's health care law - shows no signs of breaking, as each side sticks to its guns and repeats its talking points.

Democrats from Obama on down to the most junior lawmakers said again that the House should vote immediately on ending the partial closure of the government. Obama said House Speaker John Boehner, R-Ohio, "doesn't apparently want to see the ... shutdown end at the moment, unless he's able to extract concessions that don't have anything to do with the budget."

Boehner, in rebuttal, called on Obama to agree to negotiations on changes in "Obamacare" and steps to curb deficits, the principal GOP demands for ending the shutdown that began with the Oct. 1 beginning of the new fiscal year, and eliminating the threat of default. "Really, Mr. President. It's time to have that conversation before our economy is put further at risk," Boehner said on the House floor.

The White House has said repeatedly the president will not negotiate with Republicans until the government is fully reopened and the debt limit has been raised. But it hasn't said the debt limit measure has to be completely "clean" of add-ons.